“Let me tell you, you take on the intelligence community, they
have six ways from Sunday at getting back at you,” Schumer said.

“So even for a practical supposedly hard-nosed businessman, he’s
being really dumb to do this,” Schumer said.

Sen. Mark Warner of Virginia also expressed concerned about
Trump's casting doubt on the work of the intelligence community.

"Really wish we saw more PEOTUS respect for our intelligence
professionals," Warner said on Twitter.
"Proves the need for Congress to give the American people a
timely bipartisan probe."

In a Tuesday night tweet, Trump claimed his briefing on Russian
cyberattacks was delayed until Friday and suggested intelligence
leaders may have been trying to bolster their arguments.

"The 'Intelligence' briefing on so-called 'Russian hacking' was
delayed until Friday, perhaps more time needed to build a case.
Very strange!" Trump said
on Twitter.

A senior US intelligence official immediately refuted Trump’s
claim, saying the briefing with the heads of the NSA, CIA, DNI
and the FBI was "always" scheduled for Friday, NBC
News reported.

Since US officials determined Russia's involvement in the hacks
of Democratic Party organizations in an
attempt to help Trump win the election, the president-elect
has remained skeptical of their conclusions.

"These are the same people that said Saddam Hussein had weapons
of mass destruction," Trump's transition team said in a statement
about the CIA's finding's last month.